1. Field of the Invention
The present invention relates to a method of obtaining power usage information. More particularly, the present invention relates to a method and a system for estimating use time of electric appliances while taking a loop as a measuring unit.
2. Description of Related Art
With a growing shortage of petroleum, electric power and other natural resources, concepts of environmental protection and energy conservation gradually draw attentions. According to statistics, about 39% energy is used in living environment of human beings. Therefore, more and more buildings start to use smart meters having an energy calculation ability, so as to provide various power usage information of the living environment for a user.
Generally, to determine power consumption information of various electric appliances in the building, a most direct approach is to install a measurement device similar to a small power meter on each of the electric appliances. Moreover, to collect a power usage status of each electric appliance for analysis, a radio frequency (RF) communication device or a power line communication (PLC) device is required to be installed on the electric appliance, so as to transmit the power usage information to a rear-end platform through the communication device for analysing. However, it is obvious that when a number of the electric appliances required to be measured is excessive, to install the measuring device and the communication device on each of the electric appliances not only requires a considerable amount of manpower, but also requires a huge cost.
According to another aspect, regarding the electric appliances with embedded power measuring devices in the market, although the power usage information thereof can be obtained, it has a high cost. Besides, unless the electric appliances in the environment are all replaced, the power usage information of the old electric appliances still has to be obtained through external measuring devices and communication devices.